Type IV collagen is a specific and major component of basement membranes. Expression of type IV collagen is developmentally regulated in vivo and is inducible in certain cell cultures and, therefore, provides a valuable model for studies on the control of gene expression. Recently, we isolated cloned cDNA sequences for the Alpha1-chain of mouse type IV collagen. In the present proposal these cDNA clones will be used to isolate genes coding for mouse type IV collagen. Characterization of these genes will help to determine the amino acid sequence and elucidate structural features of type IV collagen chains as well as provide valuable new information about the evolution of collagen genes in general. It will also open up studies for the control of their tissue specific and developmentally regulated expression. We will examine the control of type IV collagen gene expression in a model system using F9 mouse teratocarcinoma cell cultures and DNA-mediated gene transfer techniques.